摘要
为进一步探讨血清肌酸激酶ＭＭ同工酶亚型在急性心肌梗塞（ＡＭＩ）中的诊断价值，１９８８年至１９９３年采用琼脂凝胶电泳方法对４５例ＡＭＩ患者血清ＭＭ＿３／ＭＭ＿１比值进行了动态观察，并与４０例同期住院患者相比较，发现在梗塞后血清ＭＭ＿３／ＭＭ＿１比值动态变化曲线呈“反Ｓ”型，即ＭＭ＿３／ＭＭ＿１达峰值并逐渐恢复到基础水平以后，继续下降并一度低于基础水平，然后再逐渐回升到基础水平（４８～１２０小时），并证明这是由于亚型（ＭＭ＿１，ＭＭ＿２，ＭＭ＿３）从血液中清除速率存在差异，使ＭＭ＿３恢复正常的同时，ＭＭ＿１仍维持在较高水平所致。故用ＭＭ＿３／ＭＭ＿１比值诊断ＡＭＩ时应注意梗塞早期存在一段相对不敏感期，尤其在合并梗塞扩展和再梗塞时更应注意。
o evaluate the diagnosis value of serum isoforms of creatinekinase MM isoenzyme(CK-MM)in acute myocardial infarction(AMI),the serial changes of three CK-MM isoforms(MM_1,MM_2 and MM_3)in the sera of 4 5 patients with AMI were determined by an agarose gel electrophoresis method and compared with 40 normal individuals. The results showed the time-activitv curve of serum MM_3/MM_1 ratio in patients was like an inverted“S”.The ratio decreased after the peak to a level even lower than normal, and then gradually returned to normal value. In the early periOd of AMI (48～120h)the MM_3/MM_1 ratio was lower than that of the normal level. The reason might be the MM_1 activity was kept at high level while MM_3 already went down to normal due to the differance of isoform clearance from blood. Thus the serial changes of serum MM_3/MM_1 ratio form an inverted“S”curve. And in that period after infarction,the serum MM_3/MM_1 ratio was no more sensitive in the early diagnosis of AMI,especially for myocardial extention and reinfarction.
